Material handling machine



Jan. 26, 1960 Filed Feb. 21, 1955 D. M. SCHWARTZ ETAL MATERIAL HANDLING MACHINE 3` Sheets-Sheet 1 ATTORNEY Jan. 26, 1960 D. M. scHwARTz ETAI- MATERIAL HANDLING MACHINE S Sheets-Sheet 2 Filed Feb. 21, 1955 INVENTORS DANIEL M. SCHWARTZ DONALD E. HENDRICKSON BY )MKM ATTORNEY 3 Sheets-Sheet 3 m m E- Jan. 26, 1960 D. M. scHwAR-rz ETAL MATERIAL HANDLING MACHINE Filed Feb. 21, 1955 4 v f w x//W s W wr s BY /v/m/ ZM ATTORNEY Unite MATERIAL HANDLNG MACHINE Application February 21, 1955, Serial No. 489,322

6 Claims. (Cl. 214-131) This invention relates to material handling machines having an overhead material handling device.

It is a principal object of the invention to provide a self-propelled machine for general handling of bulk materials including digging, lifting, transporting, and loading and, in particular, such a machine adapted for use in mines and tunnels Where low headroom and compactness are essential features.

The present invention is particularly adapted to overhead material handling machines of the type including a main frame or body, supported on ground engaging wheels or crawler tracks, supporting longitudinal extending rails or tracks which provide rolling surfaces for paired rocker arms having arcuate rolling faces, a material container secured to the paired rocker arms, and drive means for the rocker arms whereby the material container may be actuated from a low forward digging position to an upward and rearward discharge position.

Machines of this general type have found wide acceptance in the earth-moving industry as their diggingdischarge rate is extremely high since the machines do not have to be turned between the digging and the discharge portions of the digging-dicharge cycle.

Since material handling machines of this type do not require long pivotally mounted booms for transporting the material container from the forward digging to the rearward discharge position, the machines have also been widely employed in mining and tunneling operations where low headroom is an essential feature. Notwithstanding the advantageous low headroom feature of machines of this general class, it has been the constant endeavor of the industry to provide machines requiring even less headroom without sacrificing ruggedness whereby the range of use of the machines may be substantially increased.

United States Patent 2,684,162, Donald E. Hendrickson et al., issued July 20, 1954, describes and claims means for reducing the headroom requirements of overhead material handling machines by shaping the curved surfaces of the rocker arms so that the point of further extension ofthe shovel bucket traverses an extended rectilinear path between the low forward digging position and the upwardly and rearwardly discharge position.

The present invention provides means for reducing the headroom requirements of overhead material handling machines which may be advantageously employed on a wide variety of overhead material handling machines including the low headroom overhead loader described in United States Patent 2,684,162.

A further object is to provide such a device whereby the rolling path of the overhead rocker arms may be substantially lowered without reducing the necessary strength in the rail elements supporting the rocker arms.

A further object is to provide a novel rocker arm rail assembly including sloped contact surfaces between the rail members and the rocker arms to assist in centering the rocker arms during the digging-discharge cycle.

2,922,536 Patented Jan. 26, 1960 riice A further object is to provide such a device that is essentially self-cleaning thereby preventing build-up of material between the rolling faces of the rocker arms and their supporting rails.

A further object is to provide a device wherein the cross-connected cables for the rocker arms are carried free and clear of the points of rolling `contact between the rocker arms and their supporting rails.

These and other objects and advantages of the present invention are provided in a material handling machine which generally comprises paired rocker members carrying a material container and having curved rolling faces and support members providing longitudinally extending upwardly directed faces engaging the curved rolling faces of the rocker members, the major load carrying strength of the support members being provided by single web elements extending upwardly from the upwardly directed faces, whereby any desired strength of the support members can be obtained without increasing the height of the machine for a given eifective roller radius and without presenting upwardly directed track grooves which in operation tend to ll with material being loaded.

The invention will be more particularly described with reference to the illustrated embodiments thereof shown in the accompanying drawings in which:

Fig. l is a side view in elevation of an overhead material handling machine in partial section having rocker arms and supporting rails constructed inaccordance with the teachingsv of this invention; y

Fig. 2 is a rear elevational View in partial section of the machine shown in Fig. l;

Fig. 3 is an enlarged fragmentary sectional view of a portion of the overhead bucket structure and supporting rail shown in Figs. l and 2; and

Figs. 4 through 7 are enlarged fragmentary sectional views of modified forms of overheadrrocker structures and their supporting rails.

Referring to Figs. l through 3, 10 is the body of an overhead material handling machine having paired lateral ground engaging crawler units 12 mounted thereto. The crawler units 12 may be mounted for independent pivotal movement relative to the body portion 10 as is well known in the art.

Paired parallel longitudinal extending rails or tracks generally designated 14 are secured along the upper side edges of the body portion 10 by brackets or the like 16, 18 and 20.

Each of the rails 14 has a longitudinally extending upwardly directed face portion '22 and a web element 24 extending generally upwardly from the upwardly directed face portion 22. Each upwardly directed face 22 of the rails 14 contacts an arcuate rolling face 26 of a rocker arm unit 28 while the upwardly extending web element 24 provides the necessary depth for strength and resistance to deiiection in the rails during the digging-discharge cycle of the rocker units, as to be more fully described hereinafter.

Each rocker unit 28 is provided with paired groov 30 and 32 which extend laterally, substantially at rail height, from the curved rolling surface 26. The grooves 30 and 32 are adapted to receive cross-connected cables 34 and 36. One end of each of the outboard cables 34 is pin-connected adjacent the rearward end of its rail 14, as at 38, while the other end is secured to its rocker arm at 40. The inboard cable 36 for each rocker unit is pinconnected at the forward end 42 of its respective rail while the other end is connected to its rocker unit at 44. These cross-connected cables aid in maintaining rolling contact between the rails and the rocker arms.

The rocker arms carry at their forward ends aA shovel bucket or the like 46 having a digging lip 48, and they are further provided with shock absorbing bumper means of the piston and cylinder type generally designated 50. The bumper means S absorb the high discharge momentum of the rocker arms and bucket when the front end 52 of each piston contacts the bumper frame generally indicated at 54 during the discharge portion of the digging-discharge cycle of the machine.

In the form of the loader shown in the application drawings, the two rocker units or arms 28 are connected together by a yoke member 56 which member also provides anchoring means at 58 for a at cable chain 60 or other flexible draft means for actuating the rocker arms and attached bucket. chain after passing over a sheave 64 rotatably supported by the body of the loader is secured to a motor driven reel 62.

In operation of the form of the loader shown in the drawings the rocker arms and attached bucket are actuated from a low forward digging position to an elevated, rearward dumping position when the flat cable chain 60 is wound upon the reel 62; the path of the digging lip 48 of the bucket is shown in dotted lines in Fig. 1 of the drawings.

From Fig. 1 it will be seen that the minimum headroom requirements of the loader is determined at the point which the tip of the digging lip 48 reaches its highest point, indicated at A, above the ground level during the digging-discharge cycle. It will further be seen that for a machine having a rocker arm with a given effective roller radius that the lower the contact points between the upwardly directed faces 22 of the rails 14 and the arcuate rolling faces 26 of the rocker arms the lower will be the headroom requirements of the machine.

It has been found that when very low headroom is required for the loading machine a few inches of raised rail becomes a very serious problem in obtaining the desired minimum headroom. For each inch that the rail section is increased in depth, for strength and resistance to deection, the overhead headroom of the loader becomes twice as much greater, since the distance from the rolling surface of the rails to the ground on the rocker arms must be increased by the same amount and this increase adds to the raised height of the rail when the rocker arms are in the overhead position. With the rocker arm and rail construction shown in Figs. 1 through 3 of the drawings, it will be seen that since the web 24 provides the major load carrying strength of each rail 14 and the cross-section of the rail adjacent the upwardly directed face 2,2 which engages the arcuate rolling face of the rocker member is kept to a minimum, very low headroom machines may be provided.

It will also be seen that with a single load supporting web member 24 the cross-connected cable 34 and 36 may be positioned laterally of the rolling surface of the rocker arms whereby damage to the cables is substantially eliminated from dirt and rocks which may accumulate on the upwardly extending faces 22 of the rails 14.

In order to substantially eliminate the collection of dirt and rocks during the digging-discharge operation the rail faces 22 of each rail is sloped downwardly away from the upstanding web 24 which aids in the automatic removal of deposited material. The sloped contact between the rails and the arcuate rolling faces of the rocker arms also provides for automatic centering of the rocker arms when the arms are cross-connected by the yoke bar S6.

With reference to Fig. 4 of the drawings there is shown a modified form of rocker arm and rail construction particularly adapted for use on overhead loading machines not provided with a yoke bar interconnecting the paired rocker arms. In this form of the invention, the main body 10 of the loader supports paired parallel rails generally designated 70 having longitudinally extending The other end of the at cable upwardly directed faces 70a and 7Gb, and a web element '74 extending upwardly from the medial line of the rails whereby each rail has two faces which contact the paired arcuate rolling faces of the rocker arms 28'. Each rocker arm 28 is bifurcated, as at 78, to provide two arcuate rolling faces 76a and 7Gb which contact the rails longitudinal extending faces 70a and 70b respectfully during the digging-discharge cycle of the loading machine.

The faces 70a and 70b of the rail 70 are sloped downwardly from the web 74 and complementary sloping faces are provided on the bifurcated rocker arm. These sloping faces cooperate in keeping the rocker arm centered on the rail along with the upwardly extending web 74 which in addition to providing the necessary strength and resistance to deection in the rail act as guide means for the rocker arm without increasing the headroom of the machine as hereinbefore described.

The rocker arm 2S' is provided with a laterally extending portion Stl having grooves 30 and 32 adapted to receive inboard and outboard cross-connected cables as described with reference to Figs. l to 3 of the drawings.

Referring to Fig. 5 of the drawings a further modification of the invention is shown wherein a track or rail 84 is secured to the body of the material handling machine 10. The track 84 has a longitudinally extending upwardly directed face portion 86 and a web member 8S extending upwardly therefrom to provide the necessary strength and resistance to deection.

The longitudinally extending upwardly directed face portion 86 of the rail S4 engages an arcuate rolling surface 90 of the rocker arm structure 92, which structure is also provided with a depending ange portion 94 which loops over the upstanding web S8 to provide side guiding for the rocker arm. It will be noted in this form of the invention that while the flange portion 92 loops over the upstanding web 88 the rolling line of contact between the rail and the rocker arm is maintained between the surfaces 86 and 90 thus keeping the line of rolling contact at a low level maintaining overall low headroom during the digging-discharge cycle of the loader. The rocker arm 92 is provided with a laterally extending ange portion 80 provided with inboard and outboard grooves 30 and 32 as in the preceding forms of the invention.

The form of the rail 96 shown in Fig. 6 is similar to rail S4 shown in Fig. 5 except the longitudinally extendingl upwardly directed face 94 of rail 96 is sloped downwardly away from its upstanding web portion 9S. The arcuate rolling face 100 of the rocker arm 92 is similarly sloped as hereinbefore described with reference to Figs. 1 to 4 of the application. The sloped faces 94 and 100 of the rail 96 and rocker arm 92' cooperates with the looped ange portion 102 in maintaining side alignment of the rocker arm with the rail.

In Fig. 7 of the drawing a further modification is shown wherein a rail N4 secured to the body of the loader 19 comprises a substantially inverted V-shaped member having paired generally upwardly directed faces 10aa and ilb which engage the sloped arcuate rolling faces lltla and llfb of bifurcated rocker arm 118. The apex of the inverted vf-shaped rail 194 projects upwardly into the space 112 between the furcations of the rocker arm whereby the height of the rolling contact between the rail and the rocker arm structure is kept to a minimum. in this form of the invention, as in the form shown in Fig. 4, the sloping faces tilde and 106i: and 108a and mdb cooperate to provide lateral guiding for the overhead bucket structure during the digging-discharge cycle. These sloping faces also aid, as hereinbcfore described, in maintainino the rolling surfaces of the rail free of accumulations of dirt and rocks.

From the foregoing description it will be seen that the hereinbefore detailed advantages of the invention are fully accomplished.

It should be understood that while several embodiments of the invention have been shown and described,

various other modications and adaptations thereof may be made by those skilled in this particular art without departing from the spirit and scope of the invention as set forth in the appended claims.

We claim:

1. In a material handling machine of the overhead rocker bucket type including a main frame, a pair of parallel rocker arms supporting a material handling device, a pair of parallel longitudinally extending rail mem* bers supported by said main frame, said rocker arms having extended outer curved surfaces for rolling engagement with said rail members throughout a diggingdischarge cycle from a low forward material gathering position adjacent one end of the main frame to an ele vated material discharge position adjacent the other end of the main frame, said rail members providing the guiding and the load supporting trackways for the rocker arms throughout their digging-discharge cycle, each of said rail members including a longitudinally extending 'flange element having a generally upwardly directed face portion upon which the curved surface of a corresponding rocker arm rolls, and means providing the major resistance to downward deflection in said rail, said means con` sisting of a single web element projecting generally npwardly from the longitudinally extending face portion of the ange elements and substantially longitudinally coextensive therewith, the path of rolling engagement between the curved rail engaging surfaces of the rocker members and the longitudinally extending upwardly directed face portions of the ilange elements of the rail members being substantially closer to the bottom of said rail members than to the top thereof whereby the required headroom of said material handling machine is decreased without decreasing the load bearing strength of said rail members.

2. The invention defined in claim 1 wherein the upwardly projecting web element of each of said rail members is positioned between the pair of rocker arms.

3. The invention defined in claim 1 wherein the up- Wardly directed face portion of each ange element has a substantial slope downwardly from its upwardly projecting web element.

4. The invention deiined in claim 1 wherein said single web element of each of the rail members is positioned between a pair of curved surfaces provided on each of said rocker arms.

5. The invention defined in claim 1 wherein said single web element of each of the rail members projects upwardly from one side only of the upwardly directed face portion of its flange element.

6. The invention defined in claim 5 wherein said upwardly directed face portion of each flange element has a substantial slope downwardly from its upwardly projecting web element. i

References Cited in the le of this patent UNITED STATES PATENTS 412,637 Libbey Oct. 8, 1889 496,555 Emery May 2, 1893 590,792 Pierpoint Sept. 28, 1897 768,920 Voynow et al. Aug. 30, 1904 860,693 Reed July 23, 1907 1,343,001 McManama June 8, 1920 2,201,671 Osgood May 21, 1940 2,201,672 Osgood May 21, 1940 2,257,027 Thomson Sept. 23, 19411 2,571,832 Chapin Oct. 16, 1951 2,668,630 Ertl Feb, 9, 1954 FOREIGN PATENTS 4,495 Great Britain Mar. 20, 1897 

